Making the 718 GT4 Faster: Chapter 4

Happy New Year gang!

We are excited to bring the latest update to our 718 GT4 project to you after a long, involuntary break from track driving. Our time frame was adjusted for us by a combination of things:

We’ve had a few developments since our last update; we’ve finalized the specs and begun production of our Street Header system for the 718 GT4. Click here to watch the video for more information on those. Spoiler alert: we were quite eager to try out the extra 30 horsepower on the race track! Take a look at the video of our best lap of the day here:

Besides the sizable power increase, we were eager to hear how the system sounded on the track. The car definitely sounds better, but we know there’s room for improvement. The factory muffler splits the flow and ends up with a bit of rasp.

At Dundon, we’re not known for “good enough”, so Charles put on his mad scientist hat and fabbed up some pieces to try a different muffler. Our standard GT3 muffler fits the space nicely, but it doesn’t play well with the factory rear diffuser. That said, we tried it anyway! The noise improvement was awesome! With a tip to tail system the 718 has a proper GT Porsche sound. However, the factory diffuser produces great downforce, and driving the car without it was… interesting. We will be developing a muffler to work with the stock aerodynamics to achieve a more desirable sound and keep the downforce our friends in Weissach worked so hard to find.

Here's the crew swapping the muffler at lunch to get that downforce back!


In our last video, we were dialing in the Motion Control Suspension, and determined we needed to adjust the spring rate to give the car more grip on the track and make it more compliant on the street. The slightly softer springs combined with a slightly more aggressive alignment definitely got us closer to the mark. A few turns on the shocks and the car is planted, predictable and fun!

We’re of two minds on the resurfacing of the track. On one hand, the new surface is awesome, smooth and fast. On the other, we’ve been working hard to collect objective data to quantify the effects of our parts. The re-pave definitely muddies the waters, but we will forge ahead and do our best to be transparent. One good thing is that we had our 991.2 GT3RS or “Lab Rat” at the track, and we can use that data to serve as a “control vehicle,” as that car has not changed since the re-pave.

Check out a flying lap from our fully outfitted 991.2 GT3RS using the new Garmin Catalyst system:

The best lap we achieved with the 718 previously was a 1:49.0 on the old pavement. The best lap for the GT3RS on the same circuit, with the same pro driver with the same setup was a 1:44.9. We saw significant improvements with the 718 GT4 after getting it dialed in. The best lap on the new configuration was 1:45.39, while the GT3RS ran a new best of 1:42.3. The lap times are significantly faster, but the main take-away for us is that the delta between the two cars is shrinking (used to be 4 seconds apart, now only 3 seconds split the two). We have a sneaking suspicion that the car will go even faster with a few more suspension tweaks.

We forge ahead with our development on this project, with continued fine-tuning of the suspension, the development of an Inconel megaphone rear section and a Dundon Lifetime muffler, and the addition of a track-ready aero package to continue making the 991 GT3 RS owners nervous!

Sneak peek of the forthcoming Inconel megaphone rear section: